Method for the manufacturing of snappers for snap rings



Aug. 28, 1928. 1,682,074

METHOD FOR THE MANUFACTURING B. FORSTER OF sNAFPERs FOR SNAP RINGS Filed March ll, 1926 Patented Aug. 28 i928 UNITE STATES PATENT OFFICE.

BERNHABD Fi BSTER, F IPFORZHEIM, GERMANY.

METHOD FOR THE MANUFACTURING OF SNAPP-ERS FOR SNAP BIN GS.

Application filed March 11, 1926, Serial No. 93,976, and in Germany March 16, 1925.

This invention relates to a method for the production of snappers having a head on one side such as used in connection with unslit snap-rings. Y

Fig. 1 shows in elevation and section a wire from which the snapper is made according to the invention.

Fig. 2 shows this wire with upset end. Fig. 3 shows in side elevation the wire on the supporting plate.

, Figs. 4 and 5 show in plan View the apparatus for curving the wire respectively in the position of rest and in the position after the bending of the wire.

If the head of the snapper does not move in a guide slot of the snap-ring it is mounted on the free visible end of the snapper and serves at the same time as abutment for the latter in the locking position.

This invention relates to a method for the manufacturing of snappers having a head at one side and consisting in securely holding, during the bending a straight Wire Which has been set off near one end, in a punch in such a manner that the transverse central axis of the straight portion of thewire coincides with the axis of the punch so that, when the punch 1s penetrating into the hollow swage said straight portion of the wire is uniformly bent to both sides to form a semi-circle.

Just when the bent wire is going to come into contact with the surface of the hollow swage the set off portion comes to bear onto the end edge of a swage whereby the wire is still more securely held during the final and strongest pressure.

()n the wire, shown in Fig. 1, a closed crank 6 is produced by bending and upsetting, said crank serving as snapper-head. The straight wire 7 is then curved in such a manner, that the plan of the crank and of the curvature coincide and that the curvature extends to the same, side as the crank. This is carried out with the aid of a swage and punch. I

An apparatus for carrying out this method is shown in Figs. 3, 4 and 5.

By means of the elastic wire holder 8 the wire 7 is pressed onto the supporting plate 9. Prior to entering into the hollow swage 10 the wire encounters the fork-shaped counterholder 12 which is under the control of a spring 11 and which ensures the wire 7 against lateral displacement during the gradual curving of the wire 7 produced by the punch 13 penetrating into the hollow swage 10. The crank 6 remains during the bending outside the range of the hollow swage.

The crank may be of any convenient shape and the arms of the upset portion may be flattened during the upsetting or shaped to form a kind of pean knob or to form a cylindrical studm order to present a better bearing surface for the nail of the finger at the pushing back of the snapper.

The new working method does not only avoid the treatment in fire but also any waste so that the cost of manufacturing is considerably reduced. The rolling fibre extends further over the entire length of the snapper which thus becomes very resistant.

I claim 1. A method of manufacturing snappers for unslit snap-rings from wire of circular cross section by means of a punch and of a hollow swage, consisting in securely holding during the bending a straight wire, which has been set-off near one end, in a punch in such a manner that the transverse central axis of the straight portion of said wire coincides with the axis of the punch so that when said punch is penetrating into the hollow swage the straight portion of the wire is uniformly bent to both sides to form a semi-circle.

2. A method of manufacturing snappers- -for unslit snap-rings from wire of circular cross section by means of a punch and of a hollow swage, consisting in securely holding during the bending a straight wire, which has been set-ofl' near one end, in a punch in such a manner that the transverse central axis of the straight portion of said wire coincides with the axis of the punch so that when said punch is penetrating into the hollow swage the straight portion of the wire is uniformly bent to both sides to form a semi-circle, the set 011' portion of the wire coming into contact with the outer edge of the hollow swage at the moment when the straight portion of the wire in being bent comes into contact with the surface of said swage whereby the wire is securely held while the final and strongest pressure is being exerted.

In testimony whereof I aflix my signature BERNHARD roRs'rER. 

